Abaixo segue um passo a passo de como configurar o DBCP (pool de conexões) do Tomcat 6.0 para o Oracle XE
< Resource name="jdbc/myoracle" auth="Container"
type="javax.sql.DataSource" driverClassName="oracle.jdbc.OracleDriver"
url="jdbc:oracle:thin:@127.0.0.1:1521:mysid"
username="scott" password="tiger" maxActive="20" maxIdle="10"
maxWait="-1" />
< description >Oracle Datasource example< /description >
< res-ref-name >jdbc/myoracle< /res-ref-name >
< res-type >javax.sql.DataSource< /res-type >
< res-auth >Container< /res-auth >
< /resource-ref >
Context initContext = new InitialContext();
Context envContext = (Context)initContext.lookup("java:/comp/env");
DataSource ds = (DataSource)envContext.lookup("jdbc/myoracle");
Connection conn = ds.getConnection();
//etc.
REFERÊNCIA